Monitoring of ionized magnesium in hemodialysis patients: A useful tool to allow a personalized prescription of dialysate composition.

BACKGROUND AND AIMS: The dialysate magnesium (Mg) concentration is a major determinant of Mg balance in hemodialysis. This study aimed to assess the systemic variations of total (tMg) and ionized Mg (iMg) during a dialysis session using acetate or citrate fluids and 0.5 or 0.75 mM Mg. MATERIALS AND METHODS: 134 patients in maintenance hemodialysis were assigned to a dialysis session with 4 different dialysates: acetate fluid with 0.5 mM Mg (1) or 0.75 mM Mg (2), citrate fluid with 0.5 mM Mg (3) or 0.75 mM Mg (4). Ionized form was measured by direct ion-selective electrode. RESULTS: A Mg loss was observed in both acetate (0.12 and 0.08 mmol/L) and citrate (0.13 and 0.14 mmol/L for tMg and iMg, respectively) fluid groups containing 0.5 mM Mg. The use of acetate and citrate dialysates with 0.75 mM Mg led to a significant median intra-dialytic increase of 0.15 and 0.08 mmol/L for tMg, respectively. A significant augmentation in iMg concentration with acetate (0.11 mmol/L) but not with citrate dialysate (0.02 mmol/L) was observed. CONCLUSION: While a dialysate Mg concentration at 0.5 mM leads to a negative balance, increasing the concentration to 0.75 mM significantly raises post-dialysis circulating Mg. Monitoring of iMg should allow a personalized prescription in dialysate Mg.

Cystatin C for kidney function assessment in patients with facioscapulohumeral muscular dystrophy.

BACKGROUND AND AIMS: Muscle mass (MM) impairment observed in facioscapulohumeral muscular dystrophy (FSHD) may bias estimated glomerular filtration rate (eGFR) based on creatinine (eGFRcreat). eGFR based on cystatin C (eGFRcys), produced by all nucleated cells, should be an interesting alternative. Main objectives were to compare eGFRcreat and eGRFcys for chronic kidney disease (CKD) staging and for annual eGFR evolution. Secondary objective was to analyse creatinine, cystatin C with measured MM. MATERIAL AND METHODS: During 4 years, 159 FSHD patients having one or more creatinine and cystatin C measurements (total samples: n = 379), with MM determination by bio-impedancemetry during their follow-up were included. eGFR were determined with CKD-Epi and EKFC equations. RESULTS: On first examination samples, mean eGFRcys was significantly lower than mean eGFRcreat of 25.5 and 17.9 ml/min/1.73 m2 using CKD-Epi and EKFC equations, respectively. 53.5% (CKD-Epi) and 59.1% (EKFC) of agreement were obtained when using eGFRcys instead of eGFRcreat with reclassifications occurring mainly towards more severe stages. Age was correlated with cystatin C but not with creatinine, MM was correlated with creatinine but not with cystatin C. eGFR decreases > 1 ml/min/1.73 m2 were more important when using eGFRcys instead of eGFRcreat (CKD-Epi: 37.5 vs 15.4%, p < 0.001; EKFC: 34.6 vs 20.2%, p < 0.01). CONCLUSION: Cystatin C which is independent of MM appears as a promising candidate biomarker for CKD diagnosis and follow-up in FSHD patient.

Optimization of Patient Management in the Gynecology Emergency Department Using Point-of-Care Beta hCG.

Background: Point-of-care testing (POCT) provides shorter turn-around times and, in many cases, potentially improves medical decision making. The AQT90 FLEX® benchtop immunoanalyzer (Radiometer Medical ApS, Copenhagen, Denmark) allows for the determination of beta-human chorionic gonadotropin (ßhCG) in 18 min. The main aim of this study was to evaluate the impact of measuring ßhCG using the AQT90 analyzer in the gynecology emergency department (ED) compared to the standard practice of using central laboratory blood testing on the patient length of stay (LOS). Methods: The evaluation consisted of two parts. The first one, conducted in the central laboratory, focused on the analytical performances of the AQT ßhCG assay. The second one, conducted in the ED, aimed at determining the impact of POCT ßhCG implementation on the timeframe in which ED patients require ßhCG assessment. Results: The within-lab imprecisions at the mean values of 17 and 287 IU/L were 2.7% and 3.7%, respectively. Using Deming regression (n = 60), the following equation was obtained in the central lab: AQT90 ßhCG = 1.1 Roche ßhCG­12.9 (r = 0.997). The implementation of POCT ßhCG in the ED significantly reduced patient LOS (145 (90−212) min vs. 205 (155−265) with and without AQT90, respectively, p < 0.001). At the 2 IU/L decision level, a 99.7% agreement with the Roche assay was reported (kappa statistics, 0.99). Conclusions: We confirm that the analytical qualities of the AQT 90 were in line with those obtained in the central lab. The implementation of the POCT ßhCG is associated with a shorter LOS in the ED due to the faster availability of the results and the faster decision-making possibilities.

Soluble urokinase-type plasminogen activator receptor strongly predicts global mortality in acute heart failure patients: insight from the STADE-HF registry.

BACKGROUND: Whether soluble urokinase-type plasminogen activator receptor (suPAR) could be a valuable prognostic indicator remains uncertain. MATERIALS & METHODS: Patients from STADE-HF (Soluble Suppression of Tumorigenesis-2 as a Help for Management of Diagnosis, Evaluation and Management of Heart Failure) were included for analysis. RESULTS: 95 patients were included. The suPAR level of expression was significantly higher in the group of patients who died at one month (7.90 ± 4.35 ng/ml vs 11.94 ± 6.86 ng/ml; p < 0.05) or 1 year (7.28 ± 4.27 ng/ml vs 11.81 ± 4.88 ng/ml; p < 0.01), but there was no significant difference according to the readmission. CONCLUSION: High suPAR levels during hospitalization for acute heart failure were highly predictive for the risk of mortality, but not the risk of readmission.

Evaluation of a new point-of-care testing for creatinine and urea measurement.

Point of care testing makes it possible to obtain results in an extremely short time. Recently, radiometer has expanded the panel of tests available on its ABL90 FLEX PLUS blood gas analyzer (ABL90) by adding urea and creatinine. The aim of this study was to verify the performance of these new parameters. This included assessment of imprecision, linearity, accuracy by comparison with central laboratory standard assays and interferences. In addition, clinical utility in a dialysis center was evaluated. Within-lab coefficients of variation were close to 2%. The mean and limits of agreement (mean ± 1.96 SD) of the difference between ABL90 and Roche enzymatic assays on cobas 8000 were 0.5 (from -1.4 to 2.3) mmol/L and -0.9 (from -19.5 to 17.8) µmol/L for urea and creatinine, respectively. The ABL90 enzymatic urea and creatinine assays met the acceptance criteria based on biological variation for imprecision and showed good agreement with central laboratory. The two assays were unaffected by hematocrit variation between 20 and 70%, hemolysis and icterus interferences. It should be noted that the relationship between lab methods and ABL90 was conserved even for high pre-dialysis values allowing easy access to dialysis adequacy parameters (Kt/V) and muscle mass evaluation (creatinine index). Rapid measurement of creatinine and urea using whole blood specimens on ABL90 appears as a fast and convenient method. Analytical performances were in accordance with our expectations without any significant interferences by hemolysis or icterus.

Long term pronostic value of suPAR in chronic heart failure: reclassification of patients with low MAGGIC score.

OBJECTIVES: Inflammation is a hallmark of heart failure (HF) and among inflammatory biomarkers, the most studied remains the C-reactive protein (CRP). In recent years several biomarkers have emerged, such as sST2 and soluble urokinase-type plasminogen activator receptor (suPAR). This study set out to examine the relative importance of long-time prognostic strength of suPAR and the potential additive information on patient risk with chronic HF in comparison with pronostic value of CRP and sST2. METHODS: Demographics, clinical and biological variables were assessed in a total of 182 patients with chronic HF over median follow-up period of 80 months. Inflammatory biomarkers (i.e., CRP, sST2, and suPAR) were performed. RESULTS: In univariate Cox regression analysis age, NYHA class, MAGGIC score and the five biomarkers (N-terminal pro brain natriuretic peptide [NT-proBNP], high-sensitive cardiac troponin T [hs-cTnT], CRP, sST2, and suPAR) were associated with both all-cause and cardiovascular mortality. In the multivariate model, only NT-proBNP, suPAR, and MAGGIC score remained independent predictors of all-cause mortality as well as of cardiovascular mortality. Risk classification analysis was significantly improved with the addition of suPAR particularly for all-cause short- and long-term mortality. Using a classification tree approach, the same three variables could be considered as significant classifier variables to predict all-cause or cardiovascular mortality and an algorithm were reported. We demonstrated the favorable outcome associated with patients with a low MAGGIC score and a low suPAR level by comparison to patients with low MAGGIC score but high suPAR values. CONCLUSIONS: The main findings of our study are (1) that among the three inflammatory biomarkers, only suPAR levels were independently associated with 96-month mortality for patients with chronic HF and (2) that an algorithm based on clinical score, a cardiomyocyte stress biomarker and an inflammatory biomarker could help to a more reliable long term risk stratification in heart failure.

Dynapaenia and sarcopaenia in chronic haemodialysis patients: do muscle weakness and atrophy similarly influence poor outcome?

BACKGROUND: Sarcopaenia, defined as a decline in both muscle mass and function, has been recognized as a major determinant of poor outcome in haemodialysis (HD) patients. It is generally assumed that sarcopaenia is driven by muscle atrophy related to protein-energy wasting. However, dynapaenia, defined as weakness without atrophy, has been characterized by a different disease phenotype from sarcopaenia. The aim of this study was to compare the characteristics and prognosis of sarcopaenic and dynapaenic patients among a prospective cohort of chronic HD (CHD) patients. METHODS: Two hundred and thirty-two CHD patients were enrolled from January to July 2016 and then followed prospectively until December 2018. At inclusion, weakness and atrophy were, respectively, evaluated by maximal voluntary force (MVF) and creatinine index (CI). Sarcopaenia was defined as the association of weakness and atrophy (MVF and CI below the median) while dynapaenia was defined as weakness not related to atrophy (MVF below the median, and CI above the median). RESULTS: From a total of 187 prevalent CHD patients [65% of men, age 65.3 (49.7-82.0) years], 44 died during the follow-up period of 23.7 (12.4-34.9) months. Sarcopaenia and dynapaenia were observed in 33.7 and 16% of the patients, respectively. Compared with patients with sarcopaenia, patients with dynapaenia were younger and with a lower Charlson score. In contrast, mortality rate was similar in both groups (38 and 27%, respectively). After adjustment for age, sex, lean tissue index, serum albumin, high-sensitivity C-reactive protein (hs-CRP), haemoglobin (Hb), normalized protein catabolic rate (nPCR), dialysis vintage and Charlson score, only patients with dynapaenia were at increased risk of death [hazard ratio (HR) = 2.99, confidence interval 1.18-7.61; P = 0.02]. CONCLUSIONS: Screening for muscle functionality is highly warranted to identify patients with muscle functional impairment without muscle atrophy. In contrast to sarcopaenia, dynapaenia should appear as a phenotype induced by uraemic milieu, characterized by young patients with low Charlson score and poor prognosis outcome independently of serum albumin, hs-CRP, Hb, nPCR and dialysis vintage.

Analytical evaluation of the novel VITROS BRAHMS procalcitonin immunoassay.

To determine the analytical performance of Novel VITROS BRAHMS Procalcitonin Immunoassay on VITROS 3600 and correlation with BRAHMS PCT sensitive KRYPTOR reference method. Analytical performances including imprecision studies, linearity, limit of detection (LoD) and determination of hemolysis index were performed for VITROS BRAHMS PCT assay. Imprecision was assessed on plasma pool and internal control with 2 levels. The method comparison was performed using 162 plasma obtained from clinical departments. The total imprecision was acceptable and all CV were <5%. The LoD was in accordance with manufacturer's claims. The equation of linearity in the lower range was found to be y = 1.0014x - 0.0091, with r2 = 1. No interference to hemoglobin up to 11 g/L was observed. Correlation studies showed a good correlation between PCT measurements using VITROS BRAHMS PCT assay against KRYPTOR system including for values lower than 2 µg/L. The novel VITROS BRAHMS PCT assay from OrthoClinical Diagnostics shows analytical performances acceptable for clinical use. In addition, the concordance with KRYPTOR method was fine at all clinical cut-offs.

Multimarker approach including CRP, sST2 and GDF-15 for prognostic stratification in stable heart failure.

AIMS: Inflammation and cardiac remodelling are common and synergistic pathways in heart failure (HF). Emerging biomarkers such as soluble suppression of tumorigenicity 2 (sST2) and growth differentiation factor-15 (GDF-15), which are linked to inflammation and fibrosis process, have been proposed as prognosis factors. However, their potential additive values remain poorly investigated. METHODS AND RESULTS: Here, we aimed at evaluating inflammatory and remodelling biomarkers to predict both short-term and long-term mortality in a population with chronic HF in comparison with other classical clinical or biological markers (i.e. N terminal pro brain natriuretic peptide, hs-cTnT, C-reactive protein) alone or using meta-analysis global group in chronic HF risk score in a cohort of 182 patients followed during 80 months (interquartile range: 12.3-90.0). Proportional hazard assumption does not hold for sST2 and C-reactive protein, and follow-up was split into short term (less than 1 year), midterm (between 1 and 5 years), and long term (after 5 years). In univariate analysis, C-reactive protein and sST2 were predictive of short-term mortality but not of middle term and long term whereas GDF-15 was predictive of short and mid-term but not of long-term mortality. In a multivariate model after adjustment for meta-analysis global group in chronic HF score including the three markers, only sST2 was predictive of short-term mortality (P = 0.0225), and only GDF-15 was predictive of middle term mortality (P = 0.0375). None of the markers was predictive of long-term mortality. CONCLUSIONS: Our results demonstrate that both sST2 and GDF-15 significantly improve the prognosis evaluation of HF patients and suggest that the value of GDF-15 is more sustained overtime and could predict middle term events.

Determination of hemolysis cut-offs for biochemical and immunochemical analytes according to their value.

Background All general biochemistry instruments allow the measure of hemolysis index (HI), and suppliers provide an acceptable HI for each assay without consideration of the analyte value or its clinical application. Our first objective was to measure the impact of hemolysis degree on plasma biochemical and immunochemical analytes to determine the maximum allowable HI for each of them using four calculation methods as significant bias in comparison to manufacturer's data. The second objective was to assess whether the maximum allowable HI varied according to the analyte values. Methods Twenty analytes were measured in hemolyzate-treated plasma to determine the HI leading to a significant change compared to baseline value. Analytes were assessed at one (3 analytes), two (5 analytes) and three (12 analytes) values according to their sensitivity to hemolysis and their clinical impact. We used four calculation methods as significant limit from baseline value: the total change limit (TCL), the 10% change (10%Δ), the analytical change limit and the reference change value. Results Allowable HI was significantly different according to the threshold chosen for most analytes and was also dependent on the analyte value for alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, iron, haptoglobin and high sensitivity troponin T. No hemolysis interference was observed for albumin, creatinine, C-reactive protein, and procalcitonin even at an HI value of 11 g/L. Conclusions This study highlights that TCL is the most appropriate calculation method to determine allowable HI in practice for biochemical and immunochemical parameters using Cobas 8000© from Roche Diagnostics. In addition, different allowable HI were found according to analyte value leading to optimization of resampling to save time in patient care.

Estimation of residual renal function using beta-trace protein: Impact of dialysis procedures.

Beta-trace protein (BTP), a low molecular weight protein of 23-29 kDa, has been proposed as a promising biomarker to estimate residual renal function (RRF) in patients on maintenance hemodialysis (HD). Indeed, BTP is cleared by native kidney but not during conventional HD session. By contrast, the removal rate of BTP using convective processes (mainly hemodiafiltration [HDF]) and peritoneal dialysis (PD) has been little or not investigated. Therefore, an aim of this study was to evaluate the impact of dialysis procedures (high-flux HD, on-line post-dilution HDF and PD) on BTP removal in comparison with beta-2 microglobulin (B2M) and cystatin C (CYSC) removals after a single session. In addition, the ability of BTP to predict RRF in PD was assessed. This observational cross-sectional study included a total of 82 stable chronic kidney disease patients, 53 patients were on maintenance dialysis (with n = 26 in HD and n = 27 in HDF) and 29 were on PD. Serum concentrations of BTP, B2M, and CYSC were measured (a) before and after a single dialysis session in HD and HDF anuric patients to calculate reduction percentages, (b) in serum, 24-hour-dialysate and 24-hour-urine in PD patients to compute total, peritoneal, and urinary clearance. RRF was estimated using four equations developed for dialysis patients without urine collection and compared to the mean of the urea and creatinine clearances in PD. The concentrations of the three studied molecules were significantly reduced (P < .001) after dialysis session with significantly higher reduction ratio using HDF compared to HD modality (P < .001): BTP 49.3% vs 17.5%; B2M 82.3% vs 69.7%; CYSC 77.4% vs 66% in HDF and HD, respectively. In non-anuric PD patients, B2M and CYSC were partly removed by peritoneal clearance (72.3% and 57.6% for B2M and CYSC, respectively). By contrast, BTP removal by the peritoneum was negligible and a low bias for the BTP-based equation to estimate RRF (-1.4 mL/min/1.73 m2 ) was calculated. BTP is significantly removed by high-flux HD or HDF, thereby compromising its use to estimate RRF. By contrast, BTP appears as a promising biomarker to estimate RRF in PD patients since it is not affected by peritoneal clearance, unlike B2M and CYSC, and it is well correlated to RRF.

Analytical performances of a novel point-of-care procalcitonin assay.

OBJECTIVES: We report the analytical performances of a new point-of-care (POC) procalcitonin (PCT) fluorescence immunoassay that uses the AFIAS-6© system from Boditech and its concordance with results of the standard method Kryptor Compact plus from the central laboratory. DESIGN: and methods: Analytical performances including imprecision studies, limit of blank (LoB), limit of detection (LoD) and limit of quantification (LOQ) were determined. The method comparison was performed using plasma vs. whole blood for Kryptor CompactPlus© vs. AFIAS-6©, respectively. RESULTS: The total imprecision was far from the CV of 4.5% claimed by the manufacturer and close to 10%, for levels of PCT at 0.4 and 8.3 µg/L. The LoD of this novel PCT assay was found to close to the LoD provided by the manufacturer at 0.04 µg/L. The LOQ was higher than that claimed by the manufacturer (0.1 vs 0.002, respectively). The equation of linearity in the lower range was found to be y = 1.056x - 0.039 with r2 = 0.993 with a mean recovery percentage of 86 ±â€¯15%. Correlation studies showed a good correlation between PCT measurements using plasma on Kryptor system and on corresponding whole blood with POC reaching a bias of -0.04 in the range from 0.02 to 2 µg/L. CONCLUSION: The novel PCT assay on AFIAS-6© is an acceptable POC alternative for the diagnosis and management of sepsis at EDs to improve the flow of patients, as results are consistent with those of the standard PCT Kryptor Compact Plus© assay, despite its higher imprecision.

Interactive whiteboard use in clinical reasoning sessions to teach diagnostic test ordering and interpretation to undergraduate medical students.

BACKGROUND: Over-testing of patients is a significant problem in clinical medicine that can be tackled by education. Clinical reasoning learning (CRL) is a potentially relevant method for teaching test ordering and interpretation. The feasibility might be improved by using an interactive whiteboard (IWB) during the CRL sessions to enhance student perceptions and behaviours around diagnostic tests. Overall, IWB/CRL could improve their skills. METHODS: Third-year undergraduate medical students enrolled in a vertically integrated curriculum were randomized into two groups before clinical placement in either a respiratory disease or respiratory physiology unit: IWB-based CRL plus clinical mentoring (IWB/CRL + CM: n = 40) or clinical mentoring only (CM-only: n = 40). Feasibility and learning outcomes were assessed. In addition, feedback via questionnaire of the IWB students and their classmates (n = 233) was compared. RESULTS: Analyses of the IWB/CRL sessions (n = 40, 27 paperboards) revealed that they met validated learning objectives. Students perceived IWB as useful and easy to use. After the IWB/CRL + CM sessions, students mentioned more hypothesis-based indications in a test ordering file (p <  0.001) and looked for more nonclinical signs directly on raw data tests (p <  0.01) compared with students in the CM-only group. Last, among students who attended pre- and post-assessments (n = 23), the number of diagnostic tests ordered did not change in the IWB/CRL + CM group (+ 7%; p = N.S), whereas it increased among CM-only students (+ 30%; p <  0.001). Test interpretability increased significantly in the IWB/CRL + CM group (from 4.7 to 37.2%; p <  0.01) but not significantly in the CM-only group (from 2.4 to 9.8%; p = 0.36). CONCLUSIONS: Integrating IWB into CRL sessions is feasible to teach test ordering and interpretation to undergraduate students. Moreover, student feedback and prospective assessment suggested a positive impact of IWB/CRL sessions on students' learning.

Multilevel qualification of a large set of blood gas analyzers: Which performance goals?

BACKGROUND: Blood gas analyzers are frequently installed as point of care devices and thus allow rapid decision making. Few data are available regarding analytical performance of large sets of BGA. We aimed at evaluating 22 ABL 90 Flex Plus analyzers intended to be deployed. The evaluation was performed at the device level and at the entire set level to characterize the quality of measurements but also to ensure consistency across the devices deployed in the hospital. METHODS: Imprecision and total error were assessed for pH, pCO2, pO2, sodium, potassium, ionized calcium, glucose, lactate and oximetry parameters. Imprecision at the hospital level including between device variability was also evaluated. One of the two analyzers used in the central laboratory was correlated with a GEM Premier 4000 and a Cobas b221 analyzers. Thereafter, we tested sequentially the 20 instruments intended to be deployed in care service in comparison with the reference device. RESULTS: Heterogeneity of analytical performance across the different analyzers was low, allowing to consider the whole set as a unique analyzer. The total error was in line with performance goals. Analytical performance of the analyzers was found suitable for use in clinical practice. CONCLUSIONS: Our study is an example of the qualification of a set of point and underscores 1)The need for a unified qualification scheme when multiple analyzers are deployed simultaneously 2) analytical performance goals compatible with clinical use and the state of the art for all parameters.

Exploring collagen remodeling and regulation as prognosis biomarkers in stable heart failure.

We assessed the predictive ability of circulating biomarkers involved in collagen synthesis (procollagen type I N-terminal propeptide [PINP], and procollagen type III N-terminal propeptide [PIIINP], collagen degradation (c-terminal telopeptide of collagen type I [CTx] and mediators of cardiac fibrosis (Galectin-3 and soluble suppression of tumorigenicity 2 protein or sST2) as prognosis markers in 182 subjects with chronic heart failure (HF). In univariate analysis, all markers predicted mortality (except for PINP). A multivariate baseline model was fitted including variables potentially associated with mortality in HF patients. The baseline regression model included age, clinical data and biomarkers. We created four models from the baseline model augmented with the levels of hs-cTnT, CRP and NT-proBNP (model 1), CTx/PIIINP ratio, sST2 and Galectine-3 (model 2), NT-proBNP and sST2 (model 3) and NT-proBNP, CTx/PIIINP ratio and sST2 (model 4), to test whether these biomarkers have an incremental value for predicting mortality. After the addition of all biomarkers to the baseline model, age, CTx/PIIINP ratio and sST2 remained significant predictors. By contrast, Galectin-3 was not significantly associated with mortality. A multimarker strategy, demonstrated that the greatest prognostic improvement was attained with the combined addition of CTx/PIIINP ratio and sST2 highlighting the potential role of fibrosis pathways in risk stratification.

Analytical performances of PENIA and PETIA urinary cystatin C determination allow tubular injury investigation.

BACKGROUND: The study was designed to evaluate the analytical performances of two ERM-DA471/IFCC traceable cystatin C (CysC) reagents available on the market for urinary CysC (u-CysC) quantification. In addition, clinical relevance was assessed by measuring u-CysC in healthy controls and in patients with tubular dysfunction. METHODS: CysC in urine was measured by a particle-enhanced nephelometric immunoassay using Siemens reagents and by a particle-enhanced turbidimetric immunoassay using DiaSys reagents. Imprecision, linearity, limit of detection and limit of quantification were evaluated according to CLSI recommendations. The two methods were tested on 150 urinary samples from 50 healthy subjects, 50 HIV patients with tubular dysfunction and 50 patients who developed acute kidney acute injury. RESULTS: Within-laboratory coefficients of variations were below 4%. The lower limit of quantification of the assay was found at 0.043 and 0.046 mg/L for DiaSys and Siemens, respectively. The following Passing-Bablok regression equations were obtained: DiaSys = 0.99 Siemens + 0.00. Using Bland-Altman analysis, the mean bias was -0.004 mg/L on the analytical range between 0.02 and 1 mg/L. Median u-CysC in 50 HIV patients with tubular dysfunction and in 50 patients with AKI was higher than in control subjects. CONCLUSIONS: Both Siemens and DiaSys reagents demonstrated reliable and reproducible performances allowing easy determination of u-CysC on automated platforms in clinical practice with potential interest for the detection of tubular dysfunction.

sST2 as a New Biomarker of Chronic Kidney Disease-Induced Cardiac Remodeling: Impact on Risk Prediction.

Heart failure is the most frequent cardiac complication of chronic kidney disease (CKD). Biomarkers help identify high-risk patients. Natriuretic peptides (BNP and NT-proBNP) are largely used for monitoring patients with cardiac failure but are highly dependent on glomerular filtration rate (GFR). Soluble suppression of tumorigenicity 2 (sST2) biomarker is well identified in risk stratification of cardiovascular (CV) events in heart failure. Furthermore, sST2 is included in a bioclinical score to stratify mortality risk. The aims of this study were to evaluate (i) the interest of circulating sST2 level in heart dysfunction and (ii) the bioclinical score (Barcelona Bio-Heart Failure risk calculator) to predict the risk of composite outcome (major adverse coronary events) and mortality in the CKD population. A retrospective study was carried out on 218 CKD patients enrolled from 2004 to 2015 at Montpellier University Hospital. sST2 was measured by ELISA (Presage ST2® kit). GFR was estimated by the CKD-EPI equation (eGFR). Indices of cardiac parameters were performed by cardiac echography. No patient had reduced ejection fraction. 112 patients had left ventricular hypertrophy, and 184 presented cardiac dysfunction, with structural, functional abnormalities or both. sST2 was independent of age and eGFR (ρ = 0.05, p = 0.44, and ρ = -0.07, p = 0.3, respectively). Regarding echocardiogram data, sST2 was correlated with left ventricular mass index (ρ = 0.16, p = 0.02), left atrial diameter (ρ = 0.14, p = 0.04), and volume index (ρ = 0.13, p = 0.05). sST2 alone did not change risk prediction of death and/or CV events compared to natriuretic peptides. Included in the Barcelona Bio-Heart Failure (BCN Bio-HF) score, sST2 added value and better stratified the risk of CV events and/or death in CKD patients (p < 0.0001). To conclude, sST2 was associated with cardiac remodeling independently of eGFR, unlike other cardiac biomarkers. Added to the BCN Bio-HF score, the risk stratification of death and/or CV events in nondialyzed CKD patients was highly improved.

An hs-TNT Second Peak Associated with High CRP at Day 2 Appears as Potential Biomarkers of Micro-Vascular Occlusion on Magnetic Resonance Imaging after Reperfused ST-Segment Elevation Myocardial Infarction.

INTRODUCTION: Micro-vascular occlusion (MVO) in a myocardial infarction (MI) is associated with an increased risk of heart failure and mortality. Hs-T-troponin has a double peak kinetic after MI. The aim was to determine if this kinetic was correlated to MVO evaluated by cardiac magnetic resonance imaging (MRI) after MI. METHODS: This is a monocentric retrospective study. Inclusion criteria were hospitalization for MI, Thrombolysis In Myocardial Infarction flow 0 at coronary angiography, reperfusion within 12 h from the onset of chest pain, cardiac MRI within the first month, and a 5-days' biological follow-up with at least hs-T-Troponin and C-reactive protein (CRP). Statistics were performed using the R software. RESULTS: Ninety-eight patients were included. Fifty-three patients (54.1%) had MVO at MRI. The existence of MVO was associated with a trend of more kissing procedure during primary percutaneous coronary intervention (p = 0.06), a significantly more frequent second peak of troponin (p = 0.048), a significantly higher CRP level (p < 0.0001) and a longer time to balloon (p = 0.01). The association of CRP level above 40 mg/L at day 2 and the observation of a second peak of troponin were associated to 95% of MVO in ST-segment elevation MI patients. By contrast, in the absence of these 2 criteria, MVO was absent in 78% of the cases. This score was associated with a higher rate of hospitalisation at 2 years. CONCLUSION: A biological score integrating hs-TNT second peak and CRP might help to predict MVO and predict outcomes after reperfused MI in our population.

Physical inactivity and protein energy wasting play independent roles in muscle weakness in maintenance haemodialysis patients.

BACKGROUND: Muscle weakness is associated with increased mortality risk in chronic haemodialysis (CHD) patients. Protein energy wasting (PEW) and low physical activity could impair muscle quality and contribute to muscle weakness beyond muscle wasting in these patients. Aim of this study was to assess clinical and biological parameters involved in the reduction of muscle strength of CHD patients. METHODS: One hundred and twenty-three CHD patients (80 males, 43 females; 68,8 [57.9-78.8] y.o.) were included in this study. Maximal voluntary force (MVF) of quadriceps was assessed using a belt-stabilized hand-held dynamometer. Muscle quality was evaluated by muscle specific torque, defined as the strength per unit of muscle mass. Muscle mass was estimated using lean tissue index (LTI), skeletal muscle mass (SMM) assessed by bioelectrical impedance analysis and creatinine index (CI). Voorrips questionnaire was used to estimate physical activity. Criteria for the diagnosis of PEW were serum albumin, body mass index < 23 kg/m2, creatinine index < 18.82 mg/kg/d and low dietary protein intake estimated by nPCR < 0.80g/kg/d. RESULTS: MVF was 76.1 [58.2-111.7] N.m. and was associated with CI (ß = 5.3 [2.2-8.4], p = 0.001), LTI (ß = 2.8 [0.6-5.1], p = 0.013), Voorrips score (ß = 17.4 [2.9-31.9], p = 0.02) and serum albumin (ß = 1.9 [0.5-3.2], p = 0.006). Only serum albumin (ß = 0.09 [0.03-0.15], p = 0.003), Voorrips score (ß = 0.8 [0.2-1.5], p = 0.005) and CI (ß = 0.2 [0.1-0.3], p<0.001) remained associated with muscle specific torque. Thirty patients have dynapenia defined as impaired MVF with maintained SMM and were younger with high hs-CRP (p = 0.001), PEW criteria (p<0.001) and low Voorrips score (p = 0.001), and reduced dialysis vintage (p<0.046). CONCLUSIONS: Beyond atrophy, physical inactivity and PEW conspire to impair muscle strength and specific torque in CHD patients and could be related to muscle quality. TRIAL REGISTRATION: ClinicalTrials.gov NCT02806089.